Kinesin is associated with a nonmicrotubule component of sea urchin mitotic spindles.
نویسندگان
چکیده
Sea urchin embryos in second division have been lysed into microtubule-stabilizing buffers to yield mitotic cytoskeletons (MCSs) that consist of two mitotic spindles surrounded by a cortical array of filaments. Microtubules have been completely extracted from MCSs by incubation at 0 degrees C with Ca2+-containing buffer. An antibody to the microtubule translocator kinesin stains the spindles in MCSs and in MCSs treated with 5 mM ATP and also stains spindle-remnants of the MCSs after the microtubules have been extracted. We conclude that kinesin binds to a nonmicrotubule component in the mitotic spindle. Based on these results, we present several models of kinesin function in the spindle.
منابع مشابه
Roles of kinesin and kinesin-like proteins in sea urchin embryonic cell division: evaluation using antibody microinjection
Previous studies suggest that kinesin heavy chain (KHC) is associated with ER-derived membranes that accumulate in the mitotic apparatus in cells of early sea urchin embryos (Wright, B. D., J. H. Henson, K. P. Wedaman, P. J. Willy, J. N. Morand, and J. M. Scholey. 1991. J. Cell Biol. 113:817-833). Here, we report that the microinjection of KHC-specific antibodies into these cells has no effect ...
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This paper describes the procedures used to purify the microtubule motor, kinesin, from mitotic cells, namely sea urchin eggs and cleavage stage embryos, and describes methods for assaying its motor activity.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 84 9 شماره
صفحات -
تاریخ انتشار 1987